PHILADELPHIA (CBS) - We know that air pollution can cause health problems like increased rates of asthma and even more serious lung issues but now researchers at UCLA say there could be bigger problems.

According to the scientists, exposure to traffic-related pollution – like living near a freeway or at a busy intersection – was associated with an increased rate of three types of childhood cancer including acute lymphoblastic leukemia and ovarian and testicular cancer.

The authors warn that these findings support a relationship between pollution and cancer, but they don’t yet know if exposure to traffic causes cancer. Nevertheless it raises major concerns.